/**
  ******************************************************************************
  * @file    IAP_Main/Src/flash_if.c
  * @author  MCD Application Team
  * @version V1.6.0
  * @date    12-May-2017
  * @brief   This file provides all the memory related operation functions.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2016 STMicroelectronics</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */

/** @addtogroup STM32F1xx_IAP
  * @{
  */

/* Includes ------------------------------------------------------------------*/
#include "flash_if.h"

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Unlocks Flash for write access
  * @param  None
  * @retval None
  */
void FLASH_If_Init(void)
{
    /* Unlock the Program memory */
    HAL_FLASH_Unlock();

    /* Clear all FLASH flags */
    __HAL_FLASH_CLEAR_FLAG(FLASH_FLAG_EOP | FLASH_FLAG_PGERR | FLASH_FLAG_WRPERR);
    /* Unlock the Program memory */
    HAL_FLASH_Lock();
}

/**
  * @brief  This function does an erase of all user flash area
  * @param  start: start of user flash area
  * @retval FLASHIF_OK : user flash area successfully erased
  *         FLASHIF_ERASEKO : error occurred
  */
uint32_t FLASH_If_Erase(uint32_t start,uint32_t Size)
{
    uint32_t PageError = 0;
    FLASH_EraseInitTypeDef pEraseInit;
    HAL_StatusTypeDef status = HAL_OK;

    /* Unlock the Flash to enable the flash control register access *************/
    HAL_FLASH_Unlock();

    /* Get the sector where start the user flash area */
    if (start < FLASH_BANK1_END)
    {
        Size = Size + ((Size%FLASH_PAGE_SIZE)?FLASH_PAGE_SIZE:0);
        pEraseInit.TypeErase = FLASH_TYPEERASE_PAGES;
        pEraseInit.PageAddress = start;
        pEraseInit.Banks = FLASH_BANK_1;
        pEraseInit.NbPages =  Size/FLASH_PAGE_SIZE;
        status = HAL_FLASHEx_Erase(&pEraseInit, &PageError);
    }
    /* Lock the Flash to disable the flash control register access (recommended
       to protect the FLASH memory against possible unwanted operation) *********/
    HAL_FLASH_Lock();

    if (status != HAL_OK)
    {
        /* Error occurred while page erase */
        return FLASHIF_ERASEKO;
    }

    return FLASHIF_OK;
}

/* Public functions ---------------------------------------------------------*/
/**
  * @brief  This function writes a data buffer in flash (data are 32-bit aligned).
  * @note   After writing data buffer, the flash content is checked.
  * @param  destination: start address for target location
  * @param  p_source: pointer on buffer with data to write
  * @param  length: length of data buffer (unit is 32-bit word)
  * @retval uint32_t 0: Data successfully written to Flash memory
  *         1: Error occurred while writing data in Flash memory
  *         2: Written Data in flash memory is different from expected one
  */
uint32_t FLASH_If_Write(uint32_t destination, uint32_t *p_source, uint32_t length)
{
    uint32_t i = 0;

    /* Unlock the Flash to enable the flash control register access *************/
    HAL_FLASH_Unlock();

    for (i = 0; (i < length) && (destination <= (USER_FLASH_BANK1_END_ADDRESS-4)); i++)
    {
        /* Device voltage range supposed to be [2.7V to 3.6V], the operation will
           be done by word */
        if (HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, destination, *(uint32_t*)(p_source+i)) == HAL_OK)
        {
            /* Check the written value */
            if (*(uint32_t*)destination != *(uint32_t*)(p_source+i))
            {
                /* Flash content doesn't match SRAM content */
                return(FLASHIF_WRITINGCTRL_ERROR);
            }
            /* Increment FLASH destination address */
            destination += 4;
        }
        else
        {
            /* Error occurred while writing data in Flash memory */
            return (FLASHIF_WRITING_ERROR);
        }
    }

    /* Lock the Flash to disable the flash control register access (recommended
       to protect the FLASH memory against possible unwanted operation) *********/
    HAL_FLASH_Lock();

    return (FLASHIF_OK);
}

/**
  * @brief  Returns the write protection status of application flash area.
  * @param  None
  * @retval If a sector in application area is write-protected returned value is a combinaison
            of the possible values : FLASHIF_PROTECTION_WRPENABLED, FLASHIF_PROTECTION_PCROPENABLED, ...
  *         If no sector is write-protected FLASHIF_PROTECTION_NONE is returned.
  */
uint32_t FLASH_If_GetWriteProtectionStatus(void)
{
    uint32_t ProtectedPAGE = FLASHIF_PROTECTION_NONE;
    FLASH_OBProgramInitTypeDef OptionsBytesStruct;

    /* Unlock the Flash to enable the flash control register access *************/
    HAL_FLASH_Unlock();

    /* Check if there are write protected sectors inside the user flash area ****/
    HAL_FLASHEx_OBGetConfig(&OptionsBytesStruct);

    /* Lock the Flash to disable the flash control register access (recommended
       to protect the FLASH memory against possible unwanted operation) *********/
    HAL_FLASH_Lock();

    /* Get pages already write protected ****************************************/
    ProtectedPAGE = ~(OptionsBytesStruct.WRPPage) & FLASH_PAGE_TO_BE_PROTECTED;

    /* Check if desired pages are already write protected ***********************/
    if(ProtectedPAGE != 0)
    {
        /* Some sectors inside the user flash area are write protected */
        return FLASHIF_PROTECTION_WRPENABLED;
    }
    else
    {
        /* No write protected sectors inside the user flash area */
        return FLASHIF_PROTECTION_NONE;
    }
}

/**
  * @brief  Configure the write protection status of user flash area.
  * @param  protectionstate : FLASHIF_WRP_DISABLE or FLASHIF_WRP_ENABLE the protection
  * @retval uint32_t FLASHIF_OK if change is applied.
  */
uint32_t FLASH_If_WriteProtectionConfig(uint32_t protectionstate)
{
    uint32_t ProtectedPAGE = 0x0;
    FLASH_OBProgramInitTypeDef config_new, config_old;
    HAL_StatusTypeDef result = HAL_OK;


    /* Get pages write protection status ****************************************/
    HAL_FLASHEx_OBGetConfig(&config_old);

    /* The parameter says whether we turn the protection on or off */
    config_new.WRPState = (protectionstate == FLASHIF_WRP_ENABLE ? OB_WRPSTATE_ENABLE : OB_WRPSTATE_DISABLE);

    /* We want to modify only the Write protection */
    config_new.OptionType = OPTIONBYTE_WRP;

    /* No read protection, keep BOR and reset settings */
    config_new.RDPLevel = OB_RDP_LEVEL_0;
    config_new.USERConfig = config_old.USERConfig;
    /* Get pages already write protected ****************************************/
    ProtectedPAGE = config_old.WRPPage | FLASH_PAGE_TO_BE_PROTECTED;

    /* Unlock the Flash to enable the flash control register access *************/
    HAL_FLASH_Unlock();

    /* Unlock the Options Bytes *************************************************/
    HAL_FLASH_OB_Unlock();

    /* Erase all the option Bytes ***********************************************/
    result = HAL_FLASHEx_OBErase();

    if (result == HAL_OK)
    {
        config_new.WRPPage    = ProtectedPAGE;
        result = HAL_FLASHEx_OBProgram(&config_new);
    }

    return (result == HAL_OK ? FLASHIF_OK: FLASHIF_PROTECTION_ERRROR);
}
/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
